Ruth A. Mendonsa
The oil refining industry has a tall order to fill: monitoring and ensuring the purity and quality of its product. In the quality control laboratory at a major US oil refinery, a laboratory spectrometer with an automated sample system from Analect Instruments Inc. is filling the bill.
Oil refineries need to be able to get fast, reliable results from their quality control laboratories in the determination of physical properties of their petroleum, such as octane, cetane, Reid vapor pressure and distillation points. They also require information regarding the chemical composition of the product, including the percentage of paraffins, olefins, naphthenes, aromatics, benzene and oxygenates.
In the past, the oil company employed multiple dedicated analyzers, which took 30 minutes or more to examine a sample, and if an emergency sample was pulled for lab analysis, the wait was about an hour. If confirmation of the results was required, another hour was lost. Single-property analyzers also require a lot of sample preparation and personnel who have to be trained.
A precise, fast technique
The company found that Analect's Fourier transform infrared (FTIR) system offered several advantages over using multiple dedicated analyzers. Compared with other technologies, such as gas chromatography and other physical-property analyzers, the FTIR system provides exceptionally precise measurement of a number of physical properties and chemical components in a very short time. Analect's FTIR spectrometer can obtain results in about two minutes. In addition, a single FTIR system
replaces many single-property analyzers, and low-skilled personnel can operate the system after about two hours of training.
From lab to factory
Knowing that all lab applications would eventually be candidates for online analysis, the oil company said it was also impressed that the FTIR system can function in the heat and vibration extremes of the process environment. The patented Transept design features a moving wedge and fixed cube mirrors, and the automated sample introduction system lowers the chance of operator error. The results are validated automatically by checking that the spectra of any new unknowns are adequately fit by the model calibration.
The oil company has found the system so beneficial that it has implemented it in facilities around the world -- a sure measure of success.